Electric robot phonograph



mh 21, 1939 L. J. ANDRES ET AL 2,l51,260l

ELECTRIC ROBOT PHONOGRAPH Filed May 18, 1936 2 Sheets-Sheet l j D D D D O O O D D D O O f TTORNEY,

March 21, 1939. L, J. ANDRES ET AL 2,151,260

ELECTRI C ROBOT PHONOGRAPH Filed May 18, 1936 2 Sheets-Sheet 2 fag/U Vf ATTORNEY.

Patented Mar. V2 1, 1939 UNITED STATES PATENT OFFICE ELECTRIC ROBOT PHONOGRAPH of Michigan Application May 18, 1936, Serial No. 80,360

20 Claims.

This invention relates in general to a multiple circuit closer for use in such devices as robot phonographs, sign liashers, and the like, for electrically initiating various visual and aural effects 5 at predetermined time intervals corresponding to recorded sound sequences.

In a talking robot machine, a phonograph is used for providing the speech and the electric actuation of various devices are caused by control circuits connected to a switch mechanism which successively makes a very large number of circuit closing contacts in each cycle of its operation so that various devices may be operated substantially at any desired intervals and in synchronism with the talking record. A combined mechanism of this kind is now generally known, accepted and designated as a robot phonograph or rolophone.

An important object of the invention is in the 20., provision of an autcmatic mechanism and associated electri-ally actuated equipment wherein a number of displays may be animated and visual elects produced in synchronism with special or sound recordings previously made.

A further object of the invention is in the provision of a comparatively simple mechanism for providing a mechanically driven switch closing device which is positive and reliable in operation requiring very little fixed internal wiring, solenoids, or other electrical parts; and to provide a mechanism which is automatically restored to normal startingl condition.

Other objects and advantages will appear hereinafter, the drawings illustrating a preferred embodiment of the invention which is shown in a partially diagrammatic manner. In the drawings,

Figure l is a somewhat diagrammatic representation of a display including various electroo mechanical devices in connection with a repeating phonograph; and

Figure 2 is a wiring diagram for a portion of the mechanism shown in Figure 1.

In the operation of arobot phonograph the .records are designed to operate at approximately thirty-three and one-third revolutions per minute and each record plays from ten to fteen minutes. If three electrical contacts are made for each revolution of the record, the apparatus provides a series of electrical impulses spaced approximately three-fifths of a second apart. Thus about one hundred contacts are made each minute and a total of ten to fifteen hundred contacts for long records. This mechanism is particularly designed for repeating visual and kvaural effects such as a display where a lecture or talk is supplemented by operation of various parts at predetermined timed intervals, and after being set for any display, it is intended to repeat automatically in proper timed relation without 5 further attention thereto. Although the disc type of sound records lare used, -the apparatus will operate equally well with a repeater mechanism to reproduce .photographic recordings on nlm, or magnetic recordings on wire.

Referring now more particularly to the drawings, an example of the principal component parts is shwn diagrammatically in Fig. l and in an actual installation these parts are all combined in a single portable case having a `single power 1 5 cord which may be plugged into a convenient source of electrical power. A phonograph or record repeater mechanism 2D comprises a driving motor 2l receiving current from a suitable source of power for operating a 'turntable 22 vfor carry- 20 ing a disc record 23 centered by a turntable shaft 24. A tone arm 25 is mounted to engage a pickup needle 26 with the grooves of the record and sound currents are transmitted through conductors 2l to an amplierl 28 and thence are tranas- 25 mitted by conductors 29 and 3D to loud speakers 3l.

A rotary timing switch 32 andnlocking relays 33 are connected with each other by arcable 34 and the rotary timing switch is connected to the motor 2l by a cable 35 and with a timing panel 36 by a cable 3l. These cables contain a number of electrical conductors for making the necessary circuit connections between the parts. lEloi' a large number of loud speakers a similar iloud speaker cable 38 may be connected frorithe locking relays to the timing panel 36.

In the timing panel are a number of plug-in openings 40 designated as external connections for power, 4l for sound, 42 for a short impulse 40 circuit, and 43 for common circuits. Corresponding to the power and sound plugs are on and off plug connections 44 and 45 respectively.

For electrically connecting these plug openings are a number of jumpers or circuit connectors 46 45 whichmay be inserted at their ends into any of the plugs for making the necessary circuit connections in proper timed relation with the sound record.

Also connected to the external connection plugs 50 40 are a number of electrical operating devices which receive their power from electric supply mains 50 and5l and may comprise any number of different devices represented in Fig. 1 as an electric lamp 52 having conductors 53 and 54 joined to the current supply means; a bell 88 having conductors 88 and 81 connected to the supply means, a motor 88 having conductors 58 and 88 to the supply means, an electro-magnetic switch 8| having conductors 82 and 83 to the supply means, and such other additional, similar, or different devices electrically operated and connected in a similar way.

Extending from the rotary timing switch is an electromagnetic counter 84 connected to the timing switch by conductors 88 and having an opening 88 for exhibiting numbers in accordance with the electrical contacts or impulses which are made by the phonograph 28. This counter is used by an operator to determine the position oi' the desired excited circuit which is to be related by the timing panel, to the recorded sound.

As shown mechanically in Fig. 2 and diagrammatically in Fig. 1, the record repeater or phonograph is provided with three mechanically operated switches. One of these switches comprises a cam 18 secured to and rotatable with the turntable shaft 24 and preferably having three angular projections or lobes to engage a movable contact member 1| ior momentarily completing an electric circuit with its relatively ilxed contact 12.

' The number o! contacts per rotation may be changed to'suit diierent conditions by simply changing the cam 18 but three contacts per rotation are found satisfactory in practice.

The second switch comprises an insulated thixnble 13 carried by an arm 14' integral or directly movable with the tone arm 25 and arranged to slip between spring contact makers 18 and 18 to break contact between them and to close an electrical connection as soon as the tone arm is in proper position to engage the starting groove of the record.

The third switch comprises a cam 11 mounted upon a shait 18 or integral with a cam ior operating the tone arm 2B designed to complete one rotation for each complete cycle of the tone arm. This cam has a fiat side 18 engageable with a central spring contact arm 88 for making connection in rest position with a contact arm 8| and when raised from the rest position with a contact arm 82. In the rest position the contacts 88 and 8| complete a rotary switch reset circuit to be described later. When the tone arm reaches its start or play position the contacts 88 and 8| are opened and the contacts 88 and 82 are closed.

A battery 83 or a similar source of power is connected through one pole 84 of a manually operable two-pole switch by means oi' a conductor 85 to the central contact 88. I Conductors 82 and 18 oi the switches are connected by a conductor 88, arms 15 and 12 are connected by a conductor 81 so that the three switches are connected in series. The other arm 1| oi the timing switch is connected by a conductor 88 to a magnet winding 88 and thence through a conductor 88 to the other side or a battery 83. The other pole 84* of the two-pole switch closes aconnection for conductors 88 for the power circuit to the various operative devices. This dual or twopole switch 84-84al is manually operated and controls both the power source for operating the timing apparatus and the record repeater or phonograph. n

The timing circuits are completed by special electromagnetic rotary switches of which two or more separate switches are utilized to accomplish the desired results. The use of two -segment rotary timing switches provides 2401 (49x49) possible circuit changes during one cycle of operation. is more than enough unless records of more than twenty minutes duration are used, which would require an additional rotary switch. In Fig. 2, two separate switches 88 and 84 are represented, the ilrst having` two electrically independent circular sets of contact segments 88 and 88 and two electrically independent brushes 81 and 88 therefor, respectively. The brushes 81 and 88 are rotatable with a shaft 88 and insulated from the shaft by insulation |88. A ratchet |8| is attached to the shaft 88 and actuated by a pawl |82 connected to a pivotally mounted armature |83 attracted by the magnet winding 88. When the magnet winding is energized the armature is drawn down against tension of a-restoring spring |84 and the pawl |82 is moved down to engage the next tooth of the ratchet with which it is held in engagement by its spring |88. Each time the solenoid 88 is energized the brushes 81 and 88 are therefore moved from one contact to the next succeeding contact, the actual movement being eiected by the tension of the restoring spring |84 in drawing the amature |82 back against its stop |88.

Als'o engaged by the armature |83 is a movable contact arm |81 for making an electrical connection with a relatively ilxe'd contact arm |88 connected by a conductor |88 with the brush 81. The contacts |81 and |88 are separated when the armature |83 is attracted and as the movable contact |81 is electrically connected to the conductor 88 the energizing circuit is broken to the brush 81 until the armature is returned by its restoring spring at which time the brush 81 is moved to the next contact 85.

The second switch 84 has an exactly similar arrangement, contacts, brushes, shaft, and operating mechanism. Its magnet winding 88 however is connected at one terminal to the conductor 88 and at the other terminal to a conductor |l8 which leads to one oi the contacts 88 of switch mechanism 83, .this conductor I8 being also connected to the movable'contact arm |81 of the switch 84. The contact brushes 88 of the switches 88 and 84 are connected by conductors with the opposite side of the battery 83 to which the conductor 88 is connected.

Each of the contacts 88 ofthe switch 88 is connected to timing jacks ||2 having a plug-in terminal for each conductor, and each of the contacts 88 of the second switch 84 is connected to a timing jack H3 having corresponding plug-in connections.

At the top of Fig. 2 are shown a number of locking relays used to hold external circuits in closed position. Each of these relays comprises a pair of solenoids |28 and |2| having winding terminals |22 and |28, and |24 and |25 respectively. A double armature |28 is mounted intermediate its ends to beattracted by either one or the other of the solenoids. Above the armature are relatively fixed and movable contact arms |21 and |28 respectively, the lower one having a projection |28 adapted to be engaged by the armature |28 when one of the solenoids |2| is energized, thereby closing a circuit between the contact arms and the contact arms |21 and |28 being connected to switch` terminals |3| and |32 respectively for energizing an external circuit for controlling a lamp, motor, bell, or any other electro-motive device. A number of plug-in connectors |33, |34, |35 and |36 are provided for operating each locking'relay, each connector hav- 'I'his number of possible circuit changes ing terminals for engaging the plug-ln sockets and making an electrical connection therewith so' that they can be quickly connected and disconnected. When a locking relay receives an impulse energizing the armature to close connection between the contacts |21 and |28, an electromotive device actuated thereby remains in operation until'the opposite solenoid for that armature is energized, thus opening the contacts. By variously combining the locking relays in this way they can be actuated to operate the display devices in any desired manner or combination. Although only.four jumpers or connectorsI |33 to |36 are shown, a plurality of jumpers are used in actual practice to establish the desired circuit connections for any particular record.

As the present invention does not depend upon the specic structure of the phonograph repeater mechanism, the multiple contact rotary switches or the locking relays it is believed unnecessary to illustrate or describe actual structures in any more detail, the drawings illustrating the necessary parts of the various elements and the circuit connections for operating them.

ln operation the double pole switch 84, 84a is manually operated which closes the power circuits tothe record repeater and the device is operated by the locking relays. Operation of the phonograph repeater rotates shaft 18 and its cam 11 thereby separating contacts 80 and 8| and closing contacts 80 and 82. This completes a circuit through conductor 86 to one of the contacts 16 which is engaged by the pickup arm projection 13 held in open position when the tone arm is in its rest position. Movement of the tone arm allows the contact 15 and 16 to makecon-Y nection when the pickup arm reaches its playing position, thus closing a circuit connection through conductor 81 to one of the contacts 12. When the turntable cam 10 rotates the contacts 1| and 12 are intermittently opened and closed. Thus a circuit is closed to energize the solenoid 89 which is as follows: from battery 83 through switch 84, conductor 85, contacts 80, 82, conductor 86, contacts 16 and 15, conductor 81, contacts 12 and 1|, conductor 88 to one side of the winding 89 and thence by conductor 90 back to the other side of the battery 83. i

A single impulse thus resulting from the closing of thelcontacts 1| and 12 for each partial rotation of the phonograph record is imparted to armature |03 against spring |04 which causes pawl |02 to move the ratchet |0| of the switch 93 one step. Assuming that the brushes of al1 the rotary switches are in their initial or open position as shown, the brushes 91 and 98 are advanced one step to contact number two for each brush. At this time a circuit is closed through brush 98 which may be traced as follows: From one side of the battery 83 by conductor to brush 98,

, contact number two of switch segments 96, conduct/or l| to the solenoid winding 89 of switch 94, and thence through conductor 90 to the other side of the battery 83. This causes the actuation of the armature 1103 of rotary switch mechanism 94 which actuates the rotary switches of switch 94 one step, but the switch mechanism 94 remains in its rst step position while the switch mechanism 93 is actuated step by step for a complete rotation of its contact brushes. The next time the brush 98 of the switch mechanism 93 engages its contact number two the switch mechanism 94 is actuated another step by its ratchet mecha-- nism, and so on; thus a combination of different circuit connections is made by the brushes 98l ,tacts of the first switch are therefore shown connected to terminals |23-X and the contacts of the second switchvare shown connected to the jack terminals L|,L2, L3-LX, depending upon the number of contacts of each of the switches.4

In operating the second locking relay, for example, the jumper terminal |33 connects the second contact of the plug terminal ||2 and the relay contact |23 and the jumper |36 connects the relay contact |22 and the second switch termnal L5. Likewise jumper |34. connects the third contact of the plug terminal I2 and the relay terminal |24 whereas the jumper |35 connects the relay terminal |25 and the second switch plug terminal L3.

When the rotary switches 93 and 94 are operated by their step by step movements to such an extent that the brush 98 engages the fourth contact and the brush 98 of the first switch engages its fourth contact a circuit will be closed for energizing the second solenoid |2| as follows: From the battery 83 through conductor brush 98, and contact number four of 'switch number one to terminal 3 of plug terminal ||2, thence by jumper |34 to contact |24, solenoid 20 to contact |25, jumper, |35 to contact L3 of plug terminal H3 and thence through connected conductor to the fourth contact and brush 98 of switch number 2 and through a common return Vconductor |40 to the other side of the battery 83. This will energize the double armature |26 of the second locking relay causing it to operate its movable contact |28' to closed connection with contact |21 and thereby to close an operating circuit for any selected device which is connected to its terminals |3| and |32.

After the rotary switches have been similarly continued in a step by step movement for a predetermined time the brushes 98 will engage the second and fth contacts of switches 93 and 94 respectively, closing a similar restoring circuit through jumpers |33 and |36 to the terminals minals LI, L2, etc., of switch 94 until the tone arm of the phonograph repeater reaches the end of play on the phonograph record.

When the record is completed an automatic cut-off action takes place and due to the rotation of the shaft 18 the tone arm 25 is raised and returned to its rest position, thereby separating the contacts 15 and l16 and thus stopping the movement of the rotary switches. At the same time the control cam 11 rotates to a position as shown in Fig. 2 where the contacts 80 and 82 are separated and 80 and 8| are closed. At this time all of the switch brushes are returned to their starting or open circuit position by the following resetting clrcuit: From one side of the battery 83, through switch 84, conductor 85, contacts 80 and 8|, and a conductor |4| to the contacts 95 of switch 94, all of which are joined together by common connectors except the rest or starting conductor number one, thence by a conductor H2 Vto the similarly connected conductors 95 of switch and thence by a common return wire 90 to the other side of the battery 83. Energizing the solenoids causes intermittent vibrating movement ofV the armatures Ill, alternately making and breaking the connections between contacts |01 and |08. 'I'hus the brushes 91 of both switches are rapidly rotated in a step by step manner until they come to rest on the number one or open segment number one of each switch which is the starting position for a repetition of the cycle.

As the manual switch 84-84 remains closed the phonograph repeater will again commence to operate and the cycle of operations will be repeated. In this way robot displays combining movements oi' various parts with a talking record can be continued and repeated without man- Vual attention. 'I'he external operating circuits when once established are not disturbed and the resetting movement of the switches moves the common circuit brush od oi the last movement segment oi.' the segment rotary switch.

Although in the operation of the locking relay only a single locking and unlocking operation is described, it will be understood that in the oper, ation'of an actual installation there will be as many multiple jack connections as there are different changes in the desired operation of the device. In an actual installation the jumper or jack connections are often so numerous as to produce a maze oi' connections, a number of th'em connected to each oi' the available plug terminals but timed by their connection with the different terminals so that they will be operated in properly timed relation to the record itself. 'Ihus any desired operation of the devices is obtained and any device may be operated as long or as Irequently as desired.

Among' the advantages` of the invention are the portability and compactness f the equipment; thel possibility of using sound records of diilerent diameters, pitches. velocities, and ditierent types of records; the of jack panels and quick detachable jumpers to facilitate tim ing; the use of an electro-magnetic counter for visually locating the impulse corresponding to the recorded sound to be synchronized; the method of holding energized external display circuits a predetermined time and the possibility o! adding additional rotary switches for complex external display circuits; and the method of obtaining complete automatic operation and automatically resetting the rotary switches to starting position.

We claim:

1. An electric robophone comprising a phono- E graph, a pair of rotary multiple contact switches,

electro-responsive means for operating the switches step by step, rotary contact means carried by the phonograph for energizing the electroresponsive means a number of times as a record is played. and circuit means for making the electro-responsive means ot one switch dependent upon the step by step movement of the preceding switch.

2. In an electric robophone, a phonograph, a-

' electro-responsive means one or more times for each rotation as the record is rotated, and circuit closing means for making the electro-responsive means of each succeeding switch dependent upon the .step by step movement of the next preceding switch.

3. The combination with a phonograph, of a plurality of rotary multiple contact switches, electro-responsive means for operating each switch step by step, turntable cam switch mechanism in connection with the phonograph operated upon each rotation thereof for energizing the electro-responsive mei'ms to rotate one switch step by step for one complete rotation before the electro-responsive means of the next switch is energized to move it for each step.

- 4. In an electric robophone, a phonograph having a turntable cam switch operated by the ro- 'tatlons thereof, a plurality of rotary switches, an

electro-responsive means for operating each switch step by step, means on each switch to close a circuit to the electro-responsive means of the next switch after the first switch has moved a complete rotation in one direction, and means for quickly restoring all switches to starting position when the playing of a record is finished.

5. In an electric robophone, a phonograph having a rotatable contact closer, the contact closer being operated upon each rotation of the phonograph, a plurality of electric switches actuated by said closer, an electro-responsive step by step mechanism for each switch, means for insuring that each switch is moved one complete rotation before the next switch is advanced one step, and conductors for closing energizing circuits in timed relation with the phonograph when contacts of two switches are simultaneously engaged.

6. In an electric robophone, a phonograph having a rotatable contact closer, the contact closer being operated upon each rotation oi' the phonograph, a pair of rotary multiple contact switches actuated by said closer each having means for separately engaging the contacts, electro-responsive means actuated by the phonograph for operating the said means of each switch step by step, conductors connected to each of the contacts of each switch, and multiple jack connections for the contacts to actuate electro-responsive devices, the said connections clodngaclrcuit through corresponding contacts of adjacent switches in timed relation to the phonograph.

'1. An electric robophone for operating a number of external electro-responsive devices, -com prising a phonograph having a rotatable contact closer, the contact closer being operated upon each rotation of the phonograph, a plurality of rotary multiple contact switches actuated by said closer, means actuated by the phonograph for actuating the switches step by step, jack terminal connections for each oi' the contacts oi each switch, and detachable jumper connections from the terminal contacts to the electro-responsive devices whereby the said device is operated in timed relation with the phonograph when the switch contacts corresponding thereto are closed by the step by step movement of the switches.

.8. In an electric robophone for operating elecl tro-responsive devices, a phonograph having a rotatable contact closer, the contact closer being operated upon each rotation oi' the phonograph, a plurality of rotary multiple contact switches actuated by said closer,` terminal plug-in connections for the contacts of each switch, means in connection with the phonograph for actuating each switch separately' step by step, means for rotating one switch a predetermined amount before the next switch is operated, jumper connections for each switch to a device to be operated, the two switches being required to provide a return circuit for energizing one of the electroresponsive devices in timed relation to the phonograph depending upon the contacts which are engaged.

9. In an electric robophone for actuating electro-responsive devices, a phonograph, rotary multiple contact switches, means comprising a rotary circuit closer controlled by the phonograph for actuating each switch step by step and each succeeding switch being dependent upon a predetermined step by step movement of the next preceding switch, plug-in terminals for each separate contact of each switch, detachable jumper jacks for connecting each contact with one terminal of one electro-responsive device to be operated, and means for visually timing the impulse of the phonograph corresponding to which the operation of the electro-responsive device is to be synchronized by the jumper connection to the switches.

10. In an electric robophone for operating electro-responsive devices, rotary multiple contact switches, means comprising a rotary circuit closer controlled by the phonograph for actuating the switches step by step, means for connecting the contacts of the switches tothe devices to be' operated vin timed relation, and counter means for visually indicating the step by step impulse corresponding to which the switch connections are made for operating the electro-responsive device.

11. In an electric robophone, -a phonograph, rotary multiple contactswitches, means comprising a rotary circuit closer controlled by the phonograph and operated at each rotation thereof for operating the switches step by step, and switch means to limit the step by step movement tothe actual time that the phonograph is in playing position.

12. In an electric robophone, a phonograph having a tone arm for playing a record, rotary multiple contact switches, means controlled by the operation of the phonograph due to the rotations thereof for operating the switches step by step, and electric switch means operated by the tone arm for closing a circuit to the switch operating means only when the tone arm is in record playing position.

13. In an electric robophone, a phonograph, a pair of rotary multiple contact switches each having an electro-responsive mechanism for moving it step by step in one direction, rotary circuit closing means comprising a rotary circuit closer in connection with the phonograph and operative at each rotation thereof for energizing the step by step mechanism of the first switch, and a circuit closed by one switch at each operation thereof for energizing the step by step operating device of 'the next switch.

i4. In an electric robophone, a phonograph,

Y rotary multiple contact switches each having a plurality of sets of Acontacts and an electro-responsive device for actuating 'it step by step, means comprising a mechanical circuit closed in each rotation thereof for actuating the electroresponsive devices of the switches, and means in connection with the electro-responsive device of each switch for quickly actuating the electroresponsive device independent of the phonograph actuation thereof for restoring the switch to starting position.

15. In an electric robophone, a phonograph, rotary multiple contact switches each having an electro-responsive device for actuating it step by step, means comprising a rotary mechanical circuit closed in connection with the phonograph operativey at each rotation thereof for energizing the electro-responsive devices to operate the switches step by step and successively for regular timed operation, means in connection with the phonograph tone arm for insuring regular operation of the electro-responsive devices only when the record is being played, and an intermittent make and break connection established when the phonograph record has been played for actuating the electro-responsive devices to return the switches quickly to starting position independently of the phonograph means for controlling said electro-responsive devices.

16. In an electric robophone, a repeating phonograph, rotary multiple contact switches having an electro-responsive step by step device for each switch, means comprising a rotary mechanical circuit closed in connection with the phonograph operative at each rotation thereof for actuating the step by step devices for playing a complete record, timed means in connection with the phonograph for closing a circuit to the electro-responsive devices through the phonograph operated means for the regular step by step movement of the switches, and a circuit connection also closed by the said timing means when the playing of a record is complete for quickly actuating the step by step devices for returning the switches to starting position.

1'7. In an electric robophone, a repeating phonograph, rotary multiple contact switches each having an electro-responsive step bystep rotating device, means comprising a rotary mechanical circuit closedl in connection with the phonograph operative at each rotation thereof for closing a circuit to energize the electro-responsivedevices in timed relation to a record being played, a timed cam :for making a complete rotation for one-operation of the phonograph record, and circuit means including a switch in connection with the cam for closing the said circuit controlled bythe phonograph while the record is being played and for opening the said circuit as soon as the record playing is finished, and also for closing another circuit to the electro-responsive devices for the switches for quickly operating them to return the switches to starting position in a step by step movement.

18. In an electric robophone, a repeating phonograph, rotary multiple contact switches and an electro-responsive device for actuating each switch in a step by step movement, means comprising a rotary mechanical circuit closed in connection with thephonograph operative at each rotation thereof for actuating the electro-responsive devices to operate the switches in a timed step by step relation with respect to a record being played, and means also in connection with the phonograph for actuating the electro-responsive devices quickly in a step by step movement after the playing of the record is compleated. connection with the phonograph operative at u 19. In an electric robophone, 'a phonograph, a pair of rotary multiple contact switches, an electro-responsive device in connection with each switch for operating it in a step by step movement, means comprising a rotary mechanical circuit closer in connection with the phonograph operative at each rotation thereof ior moving one switch a complete rotation before the other switch is moved one step and in timed relation to the playing o1' the phonograph, and means opswitches and one of the electro-responsive devices for connecting them in series during the timed rotation of the phonograph as determined by the movement of the tone arm, and circuit closing means in connection with the contacts of one of the switches and the electro-responsive device of the other for closing an energizing circuit ior the electro-responsive device of the said other switch, and circuit closing means in connection with' both rotary switches and with the cam switch of the phonograph for closing circuits simultaneously to the electro-responsive device of both switches when the playing o1' a record is completed.

LLOYD J. ANDRES. GILBERT A. MAGRUDER. 

